The Simplest Possible Web Component (CustomElement)

A WebComponent (CustomElement) is an ES 6 class:


class HelloWorld extends HTMLElement { 
    connectedCallback() { 
        const message = "world";
        this.innerText = `
            hello, ${message}
        `;
    }
}
customElements.define('hello-world',HelloWorld);

which renders itself after including in a "html" page:


<!DOCTYPE html>
<html>
<body>
    <hello-world></hello-world>
    <script src="HelloWorld.js"></script>
</body>
</html>

WebComponents are supported in all recent browsers.

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